Mob not Despawning

I have been making a plugin basically a wanted plugin for gta. This is how it works, whenever a player kills another player pigman spawns in the location of the player. But if the pigman kills the player then i want them to despawn. I wrote the code of despawing but for some reason when i play ingame to test it, it doesnt despawn.
I cant find out the problem.
Whole Code : https://pastebin.com/5rmDyzd8
Despawn Code:

Code:

if(killer instanceof Monster && deader instanceof Player){      
                List<Entity> enemies = killer.getNearbyEntities(20, 20, 20);
                player.sendMessage("There are " + enemieslength + "enemies");
                enemieslength = enemies.size();
                for (int x = 0; x < enemieslength; x++)
               {
                       Entity e1 = enemies.get(x);
                       if(e1 instanceof LivingEntity){
                       ((LivingEntity)e1).setHealth(0);
                       }
            }

 

Code:

package me.bukkit.IcyFlameX;
import java.util.List;
import org.bukkit.ChatColor;
import org.bukkit.Chunk;
import org.bukkit.Location;
import org.bukkit.Material;
import org.bukkit.configuration.file.FileConfiguration;
import org.bukkit.entity.Creature;
import org.bukkit.entity.Entity;
import org.bukkit.entity.IronGolem;
import org.bukkit.entity.LivingEntity;
import org.bukkit.entity.Monster;
import org.bukkit.entity.PigZombie;
import org.bukkit.entity.Player;
import org.bukkit.World;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.entity.EntityType;
import org.bukkit.event.entity.EntityDeathEvent;
import org.bukkit.event.entity.PlayerDeathEvent;
import org.bukkit.inventory.ItemStack;

public class KillClass implements Listener {
    Wanted plugin;
    FileConfiguration config;
    int enemieslength;
    public KillClass(Wanted plugin) {
        plugin.getServer().getPluginManager().registerEvents(this, plugin);
        this.plugin = plugin;
        config =plugin.getConfig();
    }
   
    @SuppressWarnings({ "deprecation", "null" })
    @EventHandler
    public void WantedLvL(PlayerDeathEvent e) {
       
        //Player getting killed
        Entity deader = e.getEntity();
        //Player killing
        Entity killer = e.getEntity().getKiller();
       
        if(killer instanceof Player && deader instanceof Player){
            Player player = (Player) killer;
           //Increasing the Kill amount
            int killcount=0;
            String path = "Kills." + player.getName();
            if(config.contains(path)){
                killcount= config.getInt(path);
                }
            config.set(path, killcount+1);
           //Increase Wanted Level
            int wantlvls =0;
            String wantpath = "WantLvL." + player.getName();
            if(config.getInt("Kills."+ player.getName())== config.getInt("KW")){
            if(config.contains(wantpath)){
                    wantlvls=config.getInt(wantpath);
            }
                    config.set(wantpath,1);
            if(config.getInt("WantLvL."+ player.getName())==1){
                Location l = player.getLocation();//Player Location
                for(int i=0;i<config.getInt("Zombies");i++){
                    PigZombie pz = (PigZombie) l.getWorld().spawnEntity(l, EntityType.PIG_ZOMBIE);
                    pz.getEquipment().setItemInHand(new ItemStack(Material.IRON_SWORD, 1));//SpawnZombie 
                    pz.setAngry(true);   
           
            }
            }
            plugin.saveConfig();
        } //kill mob after player gets killed
            if(killer instanceof Monster && deader instanceof Player){       
                 List<Entity> enemies = killer.getNearbyEntities(20, 20, 20);
                 player.sendMessage("There are " + enemieslength + "enemies");
                 enemieslength = enemies.size();
                 for (int x = 0; x < enemieslength; x++)
                {
                        Entity e1 = enemies.get(x);
                        if(e1 instanceof LivingEntity){
                        ((LivingEntity)e1).setHealth(0);
                        }
            }
   
    }
   
}
}
}

 

When i replace killer instanceof Monster with killer instanceof Player then when i kill the other player the mobs despawn within 20 blocks but its not happening when i put monster there. As for the last 3 } i made that, if(Checking if killer s monster) statement a nested one, inside the main if which is checking if both are playera

 

Nope still its not solved, the mobs only despawn when there are no players nearby i.e unloaded chunk

Code:

package me.bukkit.IcyFlameX;
import java.util.List;

import net.milkbowl.vault.economy.Economy;

import org.bukkit.ChatColor;
import org.bukkit.Chunk;
import org.bukkit.Location;
import org.bukkit.Material;
import org.bukkit.configuration.file.FileConfiguration;
import org.bukkit.entity.Creature;
import org.bukkit.entity.Entity;
import org.bukkit.entity.IronGolem;
import org.bukkit.entity.LivingEntity;
import org.bukkit.entity.Monster;
import org.bukkit.entity.PigZombie;
import org.bukkit.entity.Player;
import org.bukkit.World;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.entity.EntityType;
import org.bukkit.event.entity.EntityDeathEvent;
import org.bukkit.event.entity.PlayerDeathEvent;
import org.bukkit.inventory.ItemStack;

public class KillClass implements Listener {
    Wanted plugin;
    FileConfiguration config;
    int enemieslength;
    public KillClass(Wanted plugin) {
        plugin.getServer().getPluginManager().registerEvents(this, plugin);
        this.plugin = plugin;
        config =plugin.getConfig();
    }
   
    @SuppressWarnings({ "deprecation", "null" })
    @EventHandler
    public void WantedLvL(PlayerDeathEvent e) {
       
        //Player getting killed
        Entity deader = e.getEntity();
        //Player killing
        Entity killer = e.getEntity().getKiller();
       
        if(killer instanceof Player && deader instanceof Player){
            Player player = (Player) killer;
           
            int killcount=0;
            String path = "Kills." + player.getName();
            if(config.contains(path)){
                killcount= config.getInt(path);
                }
            config.set(path, killcount+1);
           
            int wantlvls =0;
            String wantpath = "WantLvL." + player.getName();
            if(config.getInt("Kills."+ player.getName())== config.getInt("KW")){
            if(config.contains(wantpath)){
                    wantlvls=config.getInt(wantpath);
            }
                    config.set(wantpath,1);
            if(config.getInt("WantLvL."+ player.getName())==1){
                Location l = player.getLocation();
                for(int i=0;i<config.getInt("Zombies");i++){
                    PigZombie pz = (PigZombie) l.getWorld().spawnEntity(l, EntityType.PIG_ZOMBIE);
                    pz.getEquipment().setItemInHand(new ItemStack(Material.IRON_SWORD, 1));
                    pz.setAngry(true);   
           
            }
            }
            plugin.saveConfig();
        }
        }// end of player kill,wanted and zombie spawn method       
            if(killer instanceof Monster && deader instanceof Player){       
                 List<Entity> enemies = killer.getNearbyEntities(20, 20, 20);
                 enemieslength = enemies.size();
                 for (int x = 0; x < enemieslength; x++)
                {
                        Entity e1 = enemies.get(x);
                        if(e1 instanceof LivingEntity){
                        ((LivingEntity)e1).setHealth(0);
                        }
            }
   
    }//end of mob despawn
   

}//end of PlayerDeathEvent
}// end of Class

 

@timtower
List<Entity> enemies = killer.getNearbyEntities(20, 20, 20);
here the killer is the monster as specified by if(killer instanceof monster)
so if the player gets killed by that mob then List takes all the nearby entites within 20 blocks and sets their life to 0
So it should kill the other pig zombies which gets spawned due to
for(int i=0;i<config.getInt("Zombies");i++){
PigZombie pz = (PigZombie) l.getWorld().spawnEntity(l, EntityType.PIG_ZOMBIE);
pz.getEquipment().setItemInHand(new ItemStack(Material.IRON_SWORD, 1));
pz.setAngry(true);
But other zombies dont get killed.
Sorry for bad English.

 

@timtower in config.yml i have set the vaule to 3 for now , so whenever i killed a player , the 3 zombie pigman will spawn. To find any living entities near the killer (mob) i m doing
List<Entity> enemies = killer.getNearbyEntities(20, 20, 20);

 

@timtower What do you mean ? The list is storing the desired amount of entities found

 

@timtower any living entities

 

Shows nothing. I have no idea right now
I even tried
if(killer instanceof Monster && deader instanceof Player){
Player player= (Player) deader;
for(Entity en : player.getLocaiton.player.getChunk().getEntities()){
if(!(en instanceof Player)) {
en.remove();
}
Still nothing happens

 

It should store the entities, since i m getting all the nearby entities ? if i am not wrong

 

@IcyFlameX
Why don't you stuff the UUID of the three pigmen into a hashset, then put that in a bigger arraylist, then if a player is killed by a monster, see if any of the hashsets contain the UUID of the killer. If so, then remove all the entities in the same hashset. If any of the monsters are killed, then remove them from the hashsets too. That way, you can keep track of them when you spawn them up until the time when they die or are removed.